The present invention relates to a roller bearing lubricating device for a lateral rotary machine.
A conventional bearing lubricating device for a rotary machine of this kind is shown in FIGS. 1 and 2. In the drawings, reference numeral 1 designates a rotary shaft, reference numeral 2 designates a roller bearing which supports the rotary shaft 1, reference numerals 2a, 2b, and 2c designate an outer race, an inner race, and rollers (ball bearings), respectively, reference numeral 3 designates a bearing housing, reference numeral 4 designates an oil tank which is provided in the housing 3 and stores lubricating oil 6, and reference numeral 5 designates an oil gauge mounted in the tank 4.
The conventional lubricating device lubricates the bearing by immersing the rollers 2c of the bearing 2 directly in the lubricating oil 6 in the tank 4. In this case, the inner race 2b of the bearing 2 rotates together with the shaft 1. Thus, the rollers 2c rotate and the oil 6 is stirred due to the rotation of the rollers 2c. This stirring produces heat, oil splashes A, and waves B on the oil surface. As a result, when the rollers 2c are immersed directly in the lubricating oil in the tank 4, more oil than necessary for the purpose of lubrication is supplied to the bearing 2. When the shaft 1 is accelerated in rotation, the heat produced by stirring abruptly increases and the bearing temperature thus remarkably increases. In addition, oil splashing increases and oil leakage results. Further, surface waviness is also increased, causing great variation in the oil surface level, and as a result the gauge 5 is unable to accurately measure the oil level.
Thus, the above-described conventional lubricating device can be applied only in the low and middle speed ranges in which the D.sub.m N value which designates the empirical speed limit of the roller bearing is at most 300,000 to 400,000 or less. D.sub.m, shown in FIG. 1, is the average in mm of the inner and outer diameters of the bearing, and N is the rotational speed in RPM of the shaft.